I was looking. Through the starter system portion of my 5th gen accord maintenance manual and I noticed that when the key is turned to position II, power is given to accessories, ignition 1, and ignition 2 wires. I understand that the ignition wires power on the instruments needed during cranking, but why are there two ignition wires? Even more puzzling, ignition II is only on in key position II and not in position I (acc) or during cranking.

What's the use of this wire?

 

Check again. I think ignition-2 circuit remains on during starting. It's the ignition-1 circuit that shuts off during starting. Anyway, the reason is to switch off unneccessary loads during cranking, like radio & defoggers.